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Health Risk Assessment of Heavy Metals in the Soil of Angouran Mineral Processing Complex in Iran Полный текст
2021
Sheikhi Alman Abad, Z. | Pirkharrati, H. | Mojarrad, M.
This study aims at assessing the health-related risk of As, Co, Cr, Ni, and Cu in the soil around Angouran Mineral Processing Complex (AMPC), due to environmentally sensitive nature of the area, having agricultural activities, habitats of animal and plant species, and industrial activities integrated with each other. Soil samples have been collected from 74 points (0-20 cm) of the area and concentrations of heavy metals have been measured, using ICP-OES. The Geoaccumulation Index (Igeo), Enrichment Factor (EF), and Integrated Pollution Index (IPI) have been used to examine the pollution level. Moreover, hazard indices (HI), hazard quotient (HQ) and cancer risk (CR) have been utilized to assess the non-carcinogenic and carcinogenic health risks of heavy metals. The average concentration of heavy metals indicates that metals’ concentration in the soil have increased in the following order: Cr = Ni> As> Cu> Co. Results from Igeo, Ef, and IPI show that As and Ni are placed in the very high pollution category. The non-carcinogenic risk of dermal absorption (adults = 1.30 E + 00, children = 1.35 E + 00) of Cr and Co polluted particles turn out to be very high. In addition, the risk of cancer as a result of the ingestion of As- and Cr-contaminated soil particles is high in both of age groups, with children being 68% more likely to be at risk of cancer than adults. Therefore, actions such as soil remediation should be done to reduce the risk of exposure and protect the health of the residents, especially the farmers.
Показать больше [+] Меньше [-]The Impact of RDF Valorization on the Leachate Quality and on Emissions from Cement Kiln (Case Study of a Region in Morocco) Полный текст
2021
Ouigmane, Abdellah | Boudouch, Otmane | Hasib, Aziz | Ouhsine, Omar | Abba, El Hassan | Isaifan, Rima J. | Berkani, Mohamed
Energy recovery is a sustainable method of municipal solid waste (MSW) management. The co-incineration of refuse derived fuel (RDF) has shown several economic and environmental advantages. The objective of this research is to assess the impact of RDF recovery on leachate quality using leachate tests and calculation of greenhouse gases (GHG) reduction in the kilns of a cement plant. The qualitative results of the eluate show that there is an impact on leachate quality depending on the type of waste. The values of the chemical oxygen demand (COD), biological oxygen demand (BOD5), electrical conductivity and pH of the leachate from the raw waste after 120 hours of leaching are 29.33 gO2/kg DM, 14.00 g O2/kg DM, 4.27 ms/cm and 7.57. On the other hand, the values of the same quality parameters of the eluate generated by the waste without RDF are 19.33 g O2/kg DM, 20.67 g O2/kg DM, 2.77 ms/cm and 7.13; respectively. The calculation of GHG reduction shows that the substitution of 83,000 tonnes per year of petroleum coke by 15% of RDF (25,493 tonnes per year) can reduces 28,970 tCO2 eq.
Показать больше [+] Меньше [-]Efficiency of humic acid from various organic sources for reducing hexavalent chromium in aqueous solutions Полный текст
2021
Moradkhani, Parisa | Oustan, Shahin | Reyhanitabar, Adel | Alidokht, Leila
In this study, efficiency of humic acids (HAs) derived from various sources to reduce CrVI in aqueous solutions was compared. HAs were extracted from leonardite, peat moss, peat, cocopeat, coal, common char, biochar, vermicompost and sewage sludge. Some chemical and spectral characteristics of the extracted HAs were measured. Then, the reducing efficiency of HAs was measured and its relationship with the determined properties was investigated. To measure the reducing efficiency of HAs, a concentration of 0.1 mM CrVI (as potassium dichromate) in a sodium nitrate solution (0.03M) with a pH of 2 and in the presence of 100 mg of HA per liter was used. The experiment was conducted in three ways (symbolized by E1, E2 and E3). They differ from each other with respect to the method of phosphate buffer addition to release CrVI ions adsorbed by HA. This buffer was added to an aliquot of final extract, to the whole volume of final suspension and to initial solution containing CrVI in experiments E1, E2 and E3, respectively. According to the results, the CrVI reducing efficiency depends not only on the nature of HA but on the method of experiment. The minimum reducing efficiency was observed for common char using experiment E2 and the maximum value was for biochar and cocopeat in all three experiments. The results showed that the two factors of ΔlogK and maximum reducing efficiency in the format of a multiple regression had a significant relationship with CrVI reducing efficiency of HAs.
Показать больше [+] Меньше [-]Carcinogenic and Non-carcinogenic Health Risk Assessment of Heavy Metals in Ground Drinking Water Wells of Bandar Abbas Полный текст
2021
Farimani Raad, Hamidreza | Pardakhti, Alireza | Kalarestaghi, Hamidreza
This research evaluates the carcinogenic and non-carcinogenic risks from cadmium, lead, and zinc in Bandar Abbas groundwater sources. The samples from 25 wells were analyzed for cadmium, lead and zinc. Total lifetime cancer risk and non-cancer risk assessment from exposure to these pollutants in drinking water (ingestion, inhalation and skin routes) were conducted for people living in these villages. In these regions most of the drinking water supplied, are from these wells which shows the importance of analyzing the quality of them in order to prevent diseases and cancer risks. The highest risk from cadmium seems to be in village Dehno Paein and also this amount for lead occurs in Tifakan Tal-e Gerdu. The highest hazard index (HI) based on human health risk assessment (HHRA) model for cadmium, lead, and zinc through oral, inhalation and dermal pathways were computed as 0.005, 1.63 and 0.043 which are in Dehno Paein, Tifakan Tal-e Gerdu and Faryab. Results show that lead can lead to more cancer cases in these villages that cadmium. The total expected cancer cases from exposure to cadmium in different routes are lower than lead.
Показать больше [+] Меньше [-]No Seasonal Differences in the Emission of Microplastics from an Urban Wastewater Treatment Plant on the Southern Coast of the Caspian Sea Полный текст
2021
Alavian Petroody, Somayye Sadat | Hashemi, Seyed Hossein | van Gestel, Cornelis A.M.
This paper is the first to report on the role of a wastewater treatment plant (WWTP) in Sari, as a source of microplastics (MPs) in the Caspian Sea. Composite 270-liter/24-hour samples were taken the treated effluent of the WWTP in winter and spring, two seasons with different levels of human activity. The effluent contained 380±52.5 and 423±44.9 MPs/m3 in winter and spring, respectively, with the total numbers of MPs/m3 not differing between the two seasons. The dominant type of MPs in the effluent was microfibers with 237±68.7 and 328±33.4 per m3 in winter and spring, respectively. In both seasons, fiber sizes of
Показать больше [+] Меньше [-]Power Recovery and Sulfate Removal from Rubber Wastewater with the Novel Model Multi-Electrode Microbial Fuel Cell Полный текст
2021
Chaijak, Pimprapa | Sato, Chikashi
Microbial fuel cell (MFC) is a well-known technology that can convert contaminated substrate in the wastewater to electrical power. To gain more power output, the multi-electrode MFC was developed owing to it has a high surface area for anaerobic microbe adhesion. Here we show the multi-anode was made from the bamboo charcoal was combined with laccase-based cathode in the ceramic separator MFC for the rubber wastewater treatment and enhancing the power generation. The untreated rubber wastewater with initial COD and contaminated sulfate concentration of 3,500 mg/L and 1,100 mg/L was used as a anolyte. The 843.33±5.77 mA/m3 of CD, the 711.23±9.76 mW/m3 of PD were generated. Moreover, this system reached 83.07±3.01% of sulfate removal when it was operated at 30 °C for 12 hr. This study recommended that multi-anode with laccase based MFC can more successfully produce energy from untreated rubber wastewater. it will be greater in terms of electricity generation and sulfate removal.
Показать больше [+] Меньше [-]Identification and Characterization of Phenolic and Flavonoids Compounds Extracted from Tunisian Pomegranate Fruit Peel Exposed to Air Pollution: Gabes City, Tunisia Полный текст
2021
Ben Amor, Afef | Ben Atia Zrouga, Khaoula | Chaira, Nizar | Ben Yahia, Leila | Nagaz, Kamel
The pomegranate (Punica granatum) fruit peel exposed to mixture air pollutants were collected from two sites with different air quality around the industrial area of Gabes city, Tunisia. The first site presented the ‘Polluted site’, which is situated in the oasis close to the industrial area. While, the second site referred to the ‘Control site’ located at 37 km from the industrial area. Using HPLC ES-MS, 21 phenols were identified and quantified in methanol extract from pomegranate fruit peel. The results showed that various phytochemical substances, including phenols acids and flavonoids, were identified and quantified in the peel extract. The polyphenols content and the flavonoids contents in peel obtained from polluted site were higher than that collected from the control site. The concentrations of the identified polyphenols were ranged between 0.39 and 7803.68 mg/ kg DW. The stimulation of some free phenolic compounds such syringic acid, transfrulic acid, epicatechin, rutin and quercetin was enregistred only in peel collected from contaminated environment. The quali-qualitative changes between sites are probably related to the difference in the air quality. The increase of polyphenols could be implicated during adaptive mechanisms under air pollution. Phenolic composition changes in Punica granatum peel could be also suggested as useful approach air pollution monitoring.
Показать больше [+] Меньше [-]Characterization and Applications of Innovative Sn-doped TiO2/AC and PPy-CS/Sn-doped TiO2 Nanocomposites as Adsorbent Materials Полный текст
2021
Naser, Elham | AL-Mokaram, Ali | Hussein, Fadhela
This work explores the synthesis and characterization of two novel nanocomposites that can be used in various applications, such as aqueous solution adsorption of pollutants. The first nanocomposite consists of tin (Sn)-doped titanium dioxide (TiO2) on activated carbon, while the other one consists of polypyrole (PPy), chitosan (CS), and Sn-doped TiO2. A contrast was made of their effective adsorbent materials for the removal of Cibacron Brilliant Yellow dye from aqueous solutions. Different analytical techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray analysis (EDX), and Fourier transform - infrared (FT-IR) were used to analysis the nanocomposite samples. SEM images show that the average particle diameter of PPy-CS/Sn-doped TiO2 NC is 75 ± 3 nm, while Sn-doped TiO2/AC particles have an average diameter of 40 ± 2 nm. The greater PPy-CS/Sn-doped TiO2 nanocoposite particle diameter indicates that the polymers cover the Sn-doped TiO2 nanoparticles, which leads to higher in the diameter of the particles. The adsorption efficiency of Sn-doped TiO2/AC was higher than that of PPy-CS/Sn-doped TiO2 sample due to its smaller particle size which resulted in a higher surface area which provides more adsorption sites. However, both samples showed remarkable adsorption capacity, where the adsorption capacity of Sn-doped TiO2/AC and PPy-CS/Sn-doped TiO2 were 104 and 103 mg/g, respectively.
Показать больше [+] Меньше [-]Effect of Re-burn Fuel Stream Location on NO Reduction in a Model Pulverized Coal Combustor Полный текст
2021
Sahu, Ajay Kumar | Ghose, Prakash
I is missing this work, a computational simulation has been performed to investigate the positional effect of reburn fuel injection on NO-reburn. Reburn fuel methane is injected across the coal injection plane at different axial positions of the combustor. Various major NO source mechanisms are considered for NO formation and NO reburn mechanism is used for NO depletion. Temperature profile, species concentration are also investigated, as both NO formation and depletion rate depends on these parameters. It has been observed that, a high temperature flame exists near coal inlet, when the reburn fuel injection plane is closer to coal inlet. On the other hand, the temperature of the flame near the coal inlet decreases when the reburn fuel injection position is far away from coal inlet region. Moreover, NO sources are observed near coal inlet region, when the reburn fuel is injected closer to coal inlet. On the other hand, only Fuel-NO is observed near coal inlet, when the reburn fuel is injected away from the coal inlet. Maximum NO reduction efficiency is observed at outlet plane when reburn fuel is injected closer to inlet, whereas a relatively lower NO reduction efficiency has been observed at outlet plane when reburn fuel is injected far away from coal inlet region.
Показать больше [+] Меньше [-]Determination of the Estimated Amounts of Discarded Face Masks due to COVID 19 in Turkey Полный текст
2021
Topal, Murat | Arslan Topal, Emine Işıl
In this study, the estimated amounts of discarded face masks due to COVID 19 were investigated. In this context, the amount of waste face masks was determined separately according to the mask types used (nonwoven, meltblown, and 3-ply, pleated) and the importance of waste face masks was revealed. According to obtained data, the estimated total daily face mask use in Turkey is 72,351,638. The highest amounts of nonwoven, meltblown, and 3-ply face mask waste were determined as 26.88, 36.29, and 43.68 tonnes/day for İstanbul city, respectively. Total amounts of nonwoven, meltblown and 3-ply face mask waste in Turkey were calculated as 144.7, 195.35, and 235.14 tonnes/day, respectively. The top 5 provinces with the highest amount of waste masks are listed as follows; İstanbul (nonwoven=26.88, meltblown=36.29, 3ply=43.68 tonnes/day), Ankara (nonwoven=9.91, meltblown=13.38, 3ply=16.11 tonnes/day), İzmir (nonwoven=7.76, meltblown=10.47, 3ply=12.61 tonnes/day), Bursa (nonwoven=5.40, meltblown=7.29, 3ply=8.78 tonnes/day), and Antalya (nonwoven=4.45, meltblown=6.01, 3ply=7.23 tonnes/day), respectively. In Turkey, 91.3% of medical waste collected in health institutions in 2019 (90,920 tonnes) was sterilized and disposed of in storage areas (83,010 tonnes). 8.7% of medical waste was sent to incineration facilities and disposed (7,910 tonnes). Considering these values, 132, 178.35, and 214.7 tonnes/day of nonwoven, meltblown, and 3-ply face mask wastes can be disposed by sterilization and the remaining 12.7, 17, and 20.44 tonnes/day by incineration, respectively.
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